Robots are automated devices which are able to manipulate objects using a series of links. The links are interconnected by one or more actuator-driven robotic joints. Each joint in a typical robot represents at least one independent control variable, i.e., a degree of freedom. End-effectors are the particular manipulators used to perform a task at hand, such as grasping a work tool. Therefore, precise motion control of the robot by controlling its various robotic manipulators may be organized by the required level of task specification. The levels include object-level control, which describes the ability to control the behavior of an object held in a single or a cooperative grasp of the robot, end-effector control, i.e., control of the various manipulators such as robotic fingers and thumbs, and joint-level control. Collectively, the various control levels achieve the required mobility, dexterity, and work task-related functionality.
Dexterous robots may be used where a direct interaction is required with devices or systems specifically designed for human use, i.e., devices requiring human-like levels of dexterity to properly manipulate. The use of dexterous robots may also be preferred where a direct interaction is required with human operators, as the motion of the robot can be programmed to approximate human motion. Such robots are typically configured to operate in a well-defined or structured workspace. However, in certain evolving applications the designated workspace is relatively confined and/or unstructured, and may be shared with human operators. In such an operating environment there is an increased likelihood that contact will occur in the workspace between the robotic manipulator and an object and/or human operator.